Improvement in artificial legs



UNITED STATES R. G. LooKwooD, or BATTLE CREEK, MICHIGAN, Assis-Non ToHIMsnLIi AND o. B. JoNEs,

PATENT OFFICE.

0F SAME PLACE.

IMPROVEMENT IN ARTIFICIAL LEGS.

Specification forming part of'lletters Patent No. 50,770, dated October31, 1865.

To all whom 'it may concern:

Be it known that I, R. G. LocKwoon, of Battle Creek, Calhoun county,State of Michigan, have invented a new and Improved Artiiicial Limb; andI do hereby declare that the following is a full, clear, andexactdescription thereof, reference being had to theaccompanyingdiawiugs, making a part of this specification, in which-Figure 1-is a vertical section through the improved linib. Fig. 2 is avertical section through the limb, taken in a plane atright angles tothe section ot' Fig. 1. Fig. 3 is a view of one side of' the jointedbrace-straps. Fig. @is an enlarged view, showing the construction ot'the knee-joint. Fig. 5 is a perspective view of the foot detached fromthe ankle-joint. Fig. 6 is a view ot' the end of the lower portion ofthe leg with the-foot removed.

`Siiilar letters ot' reference indicate corresponding parts in theseveral gures.

This invention relates to certain novel-iinprovements on the artiiicivalleg for which Letters Patent were granted to Theodore Burr, the objectof which invention is to provide i'or the use of hollow shells in themanni'actuile of the upper and lower portions of the leg, in conjunctionwith stiifening and supporting straps, which constitute bearings bothfor the joints of the knee and the ankle; also, to employ'a solidknee-cap, which is received within the upper and lower sections ot' theleg, and which is attached thereto by rolling joints andconnecting-strapsor the purpose of ai'ording strength andstihess to saidportions of the leg at the knee, as will be hereinafter described. Theobject of my invention is also to connect the foot to the lower sectionof the leg by an ankle-joint of a pecnliar'construction,and to providefor setting np or tightening this joint wen it wears loose, as will behereinafter described. y

To enable .others skilled in the art to understand' my invention, I willdescribe its construction and operation. f

v In the accompanyin gdrawin gs, A represents theuppermost section ofthe lieg, which receves the stump of the natural leg'when dissectedabove the knee. B is the knee-section, and C is; the lowermost section,to which the foot D is attached bya joint, as will be having a slot, a',in its upper end, adapted t'o'r receiving a lever, b, which is pivotedat b by a pin passing through the side straps, .ll E, as shown in Figs.l and 2.' This block ay is also perforated to receive a pin, c, which lsacted upon by one arm ofthe lever b, the other arin ot' this lever,being acted upon by a strap, F, which extends upward and overthe capot' the knee-section B, and is passed out from the npper section, A,through a slot, c, shown in Fig. l.' A groove is made transverselyacross the lower end ot' the block a I'or thepurpose of receiving` apin. g, which is riveted to the lower 'extremities oi' the side straps,E E, and which receives around it a tube, g. This tube is allowed toplay-freely upon t-he pin g, and its ends are out away on the lowerside, in order to allow the pin g to rest upon bearings h li ot' thefoot D, as shown iuFig. 2. To this tube g a screw-bolt,`i, is ,secu'elyattached, which passes down through the foot D Aand receives on its enda nut, j, bymcans of which the foot ,is attached to the lower section,C, of the leg. The foot D has acavity, D,-in its bottom, to lreceive thenut4 j, and also to receive some suitable elastic substance to affordVan elastic tread. The toe-section k ofthe foot is attached in suchmanner as to admit ota free articulation while walking. l

In order to make a perfect attachment ofthe foot to the leg, the upperportion of the foot is recessed to receive within it the lower endof thesection G,- and the bottom of the recess is inclined forward andbackward from the 'bearing-points h h; so as to allow the foot to rockupon its bearing .9. I introduce small blocks of rubber, l l, into thefoot-recess to pre vent the end ot' the block a from striking a solidsubstance, and-producing jar and concusz y scrivo sion in walking. Metalsprings may be used nstead of india-rubber, but I prefer to use theatter. The two straps E E extend from the )caring-piu g to theknee-joint, at which point zheir ends are rounded and abut against the:orresponding rounded ends ot' two side straps, l E', which are securedto the upper section, A, ot' the leg. The forni of the ends of theitraps E .E E E is shown clearly in Fig. 3, wherein it will be seen thatthe rounded sur 'aces roll upon each other, so as to admit of .heflexure of the knee. The dat surfaces of ahe ends ot' these straps abutagainst each ther when the leg is not bcnt at the knee, and ircvent theknee-joint from bending or articuating' backward. The ends of the strapsE E *14 E are connected together by links mv m and )ivot-pins n u, whichlatter pass through their espective straps and enter a metal frame, G,vhich is in the form of theletter H, and which s suitably attached tothe knee-section B, as .hown in Figs. 2 and 4. The rounded surfaces ifthe ends of the straps 'are concentric with he axes of their pivots u n,and these surfaces ire prevented from slipping' by means of teeth p,which interlock with cach other-on the ides ot' the straps. l formcompound joints it the knee, for the purpose of approaching as iear aspossible to the natural articulation of .i leg'. Y

The forward portion ot' the knee-section B s rounded to conform as nearas possible to he naturel knee-cai:` and the rear side of this ection is'ti-attened to receive the H-brace G, vhich is intended forstrengthening the parts which constitute the knee-joint.

lt will be seen from 'the .above description hat the side straps, E Eand E E', forni a metallic skeleton, and that while they serve a-supports for the leg at the knee-joint, they .lso stien the shells A andC and 'serve as earings for the pin got' the ankle-joint. These trapsenable me to employ a very thin subtance for the leg-section, and th 'asafford light- ,ese and strength to the entire structure.

, The manner of attaching the toot to the lower section of the legenables me to provide for any wear of the parts composing the joint bysetting up the nutj and drawing the joint tighter when it becomes loose.

The lever b and pin c, together with the strap F, are intended formoving the foot to the proper position in walkin g. It will be seen thatwhen the leg is bent in-walking a strain comes upon the strap, its upperend being at# tached to the body, which lifts the front end of the leverb, and by so doing the pin cv is forced downward and lifts the forwardpart of the foot. This movement of the foot takes place every time theknee is slightly bent. The strap F being passed over or in front ot' theknee-section B, it serves as a very efcient knee-spring to return theleg portion C to its proper position after the knee is bent.

I employ the rocking lever and pin in the ankle-joint for the purposeot' enabling me to move the foot with a strap, F, without the necessityof attaching this strap to the foot. By so doiugI ain enabled to removethe foot from the leg at pleasure without detaching the strap from itslower fastening.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

i. Securing the ends of the straps E E and connecting-plates m m to theknee'section B by means of a traine, Gr, substantially as described.

2. Attaching the strap F to a lever, b, which acts upon the foot Dthrough the medium of a pin, e, substantially as described.

3. Connecting the strapF at its lower end to a rocking lever, b, appliedwithin the hol low section ot' the leg, substantially as described.

4.' The combination of the hollow sections A C, kneesection B, andstraps E E', constructed substantially as described.

- R. G. LOCKWOOD. `vif'itnesses:

M. B. RUssELL, JOHN MnAcHEM.

